Coaxial capillary structure and ultra-thin heat pipe structure having the same

ABSTRACT

A coaxial capillary structure and an ultra-thin heat pipe structure having the same are provided. The coaxial capillary structure is installed in an ultra-thin heat pipe and extended towards the length direction of a pipe body of the ultra-thin heat pipe, and includes: a primary transferring capillary part and a coaxially-arranged capillary part, wherein the primary transferring capillary part is composed of a plurality of fiber bundles for forming as an integral bundle, and the coaxially-arranged capillary part is formed through a plurality of weaving wires interwoven and reeled at the exterior of the primary transferring capillary part, thereby limiting each of the fiber bundles at the central portion of the coaxially-arranged capillary part for forming a compact structure. Accordingly, a better capillary transferring effect is provided.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a coaxial capillary structure,especially to a coaxial capillary structure and an ultra-thin heat pipestructure having the same.

2. Description of Related Art

The main trend for developing electronic product is to be thinner,smaller and lighter, so a heat pipe installed therein and used fordissipating or transferring heat is also required to be thinner. Forexample, an ultra-thin heat pipe has a thickness smaller than 1.5 mm

However, the thickness of the ultra-thin heat pipe is thinned, thethickness of a capillary structure installed therein has to be thinnerand narrower or there may not be enough space inside the heat pipe forforming a vapor flow channel. The capillary structure installed inside aconventional heat pipe is formed through grooves, sintering metalpowders, fiber bundles, a metal net or a combination of the above. Thecapillary structure allows a working fluid provided in the heat pipe toperform capillary transferring, but under a situation of the pipe bodyof the ultra-thin heat pipe also being required to be thinner, thecapillary transferring effect is not as efficient as a heat pipe whichis not required to be thinned, and various tests have to be run in acertain space for achieving a balance between the capillary structureand the vapor flow channel formed inside the pipe body so as to performthe desired capillary transferring capability.

There is another type of capillary structure capable of providing abetter capillary transferring effect. Take a coaxial capillary structurefor example, the coaxial capillary structure is formed through aplurality of metal wires being reeled on an axle cable with a weavingmanner for forming a strip-like shape, and the axle cable is removedafter the weaving process is finished, so an interwoven metal wire in ahollow tubular status is obtained and used for capillary transferring.However, when being installed in an ultra-thin heat pipe, theabove-mentioned hollow tubular structure has to be processed with aflattening treatment for being formed as a flat and wide capillarystructure so as to be disposed in the pipe body of the heat pipe.Accordingly, the conventional coaxial capillary structure is formedthrough interweaving the metal wires, and slits formed between the metalwires can provide the capillary transferring effect, but the hollowtubular structure formed in the central portion becomes a flat and wideor a loosened capillary structure after being processed with theflattening treatment, thus a compact capillary structure is unable to beformed; if fibers having a smaller diameter are adopted for weaving, alarger capillary force can be obtained but the tensile strength providedfor sustaining the weaving process is relatively smaller, so the wire ismore likely to be broken during the weaving process, thereby beingharder for production and the quality being unstable. Therefore, thecapillary structure installed in the ultra-thin heat pipe still has ashortage of not providing a sufficient capillary transferring effect.

Accordingly, the applicant of the present invention has devoted himselffor researching and inventing a novel structure for improving theabove-mentioned shortages.

SUMMARY OF THE INVENTION

The present invention is to provide a coaxial capillary structure and anultra-thin heat pipe structure having the same, a plurality of fiberbundles substantially arranged in parallel or woven with a non-crossingmanner are provided in the coaxial capillary structure, so the fiberbundles are formed as an integral bundle and arranged at the center ofthe coaxial capillary structure for replacing an axial cable of aconventional coaxial capillary structure; because the axle cable of theconventional coaxial capillary structure does not provide the capillaryeffect and the capillary structure is formed as a hollow tubularstructure thereby not being able to be compactly arranged, the coaxialcapillary structure of the present invention provides a better capillarytransferring effect and enhance the structural compactness, and afterthe coaxial capillary structure of the present invention is processedwith a flattening treatment for being disposed inside an ultra-thin heatpipe, a better capillary transferring effect can be provided comparingto the prior art.

Accordingly, the present invention provides a coaxial capillarystructure, which is installed in an ultra-thin heat pipe and extendedtowards the length direction of a pipe body of the ultra-thin heat pipe.The coaxial capillary structure includes a primary transferringcapillary part and a coaxially-arranged capillary part interwoven andreeled at the exterior of the primary transferring capillary part,wherein the primary transferring capillary part is composed of aplurality of fiber bundles for forming as an integral bundle, and thecoaxially-arranged capillary part is formed through a plurality ofweaving wires interwoven and reeled at the exterior of the primarytransferring capillary part, thereby limiting each of the fiber bundlesat the central portion of the coaxially-arranged capillary part forforming a compact structure.

Accordingly, the present invention provides an ultra-thin heat pipestructure having a coaxial capillary structure, which includes anultra-thin heat pipe and an above-mentioned coaxial capillary structure,wherein a vapor flow channel is formed inside a pipe body of theultra-thin heat pipe for allowing the coaxial capillary structure to bedisposed in the pipe body of the ultra-thin heat pipe and extendedtowards the length direction thereof.

BRIEF DESCRIPTION OF DRAWING

FIG. 1 is a perspective view showing the coaxial capillary structureaccording to the present invention;

FIG. 2 is a cross sectional view showing the coaxial capillary structureaccording to the present invention;

FIG. 3 is a cross sectional view illustrating the coaxial capillarystructure being installed in a ultra-thin heat pipe according to oneembodiment of the present invention;

FIG. 4 is a cross sectional view illustrating the coaxial capillarystructure being installed in a ultra-thin heat pipe according to anotherembodiment of the present invention; and

FIG. 5 is a cross sectional view illustrating the coaxial capillarystructure being installed in a ultra-thin heat pipe according to oneanother embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

Preferred embodiments of the present invention will be described withreference to the drawings.

Please refer to FIG. 1 and FIG. 2, wherein FIG. 1 is a perspective viewshowing the coaxial capillary structure according to the presentinvention; and FIG. 2 is a cross sectional view showing the coaxialcapillary structure according to the present invention. The presentinvention provides a coaxial capillary structure and an ultra-thin heatpipe structure having the same. The coaxial capillary structure 1 isinstalled in an ultra-thin heat pipe 2 (as shown in FIG. 3 or FIG. 4),and extended towards the length direction of a pipe body of theultra-thin heat pipe 2. The coaxial capillary structure 1 includes aprimary transferring capillary part 10 and a coaxially-arrangedcapillary part 11 enclosing the exterior of the primary transferringcapillary part 10.

The primary transferring capillary part 10 is composed of a plurality offiber bundles 100 being substantially arranged in parallel or woven witha non-crossing manner so as to form an integral bundle, and the fiberbundles 100 can be made of metal fibers, or a non-metal material such asglass or carbon fibers as long as the design of the capillary materialstructure and the weaving can achieve a better match. Because each ofthe fiber bundles 100 is formed as an integral bundle through beingsubstantially arranged in parallel or woven with a non-crossing manner,and the fiber bundles 100 are allowed to be tightly adjacent to eachother for forming a minimum volume, thereby providing an excellentcapillary transferring effect between the fiber bundles 100.

The coaxially-arranged capillary part 11 is formed through a pluralityof weaving wires 110 being reeled at the exterior of the primarytransferring capillary part 10 with an interweaving manner, and theweaving wires 110 can be made of metal wires such as copper wires, or anon-metal material such as glass or carbon fibers as long as the designof the capillary material structure and the weaving can achieve a bettermatch; the material of which the weaving wire 110 is made can be thesame or different from the material of which the fiber bundle 100 of theprimary transferring capillary part 10 is made. Because of being formedthrough a coaxially arranging manner, the coaxially-arranged capillarypart 11 is enabled to be reeled at the exterior of the primarytransferring capillary part 10 with an interweaving manner, and theprimary transferring capillary part 10 is able to be limited at thecentral portion of the coaxially-arranged capillary part 11 therebyforming a compact structure, and slits formed between the fiber bundles100 of the primary transferring capillary part 10 are able to be morecompact, so an excellent capillary transferring effect and a better heattransferring effect can be provided between the fiber bundles 100.

As shown in FIG. 2, according to this embodiment provided by the presentinvention, the outer diameter of each of the fiber bundles 100 issmaller than the outer diameter of each of the weaving wires 110, so theouter portion of the coaxial capillary structure 1 is formed with fibershaving a relatively larger diameter, a better tensile strength isprovided during the weaving process and the situation of wires beingbroken is less likely to happen during the weaving process, therebyproviding an easier production and stable quality. It is understood thatthe outer diameter of each of the fiber bundles 100 can be the same asthe outer diameter of each of the weaving wires 110, because the fiberbundles 100 are formed through being substantially arranged in parallelor woven with a non-crossing manner, under a situation of the totalamounts of the fibers being the same, the provided woven structure isstill formed with a minimum volume and cross sectional area, therebyoccupying the minimum space of a vapor flow channel and providing theminimum flow resistance; so with the structure having the fiber bundles100, the central portion of the coaxial capillary structure 1 is enabledto be more compact for enhancing the capillary transferring effect.

Please refer to FIG. 3, which is a cross sectional view illustrating thecoaxial capillary structure being installed in a ultra-thin heat pipeaccording to one embodiment of the present invention; the pipe body ofthe ultra-thin heat pipe 2 is processed with a flattening treatment forobtaining a desired thickness (mostly smaller than 0.6 mm), and formedwith a bottom wall 20 and a top wall 21 corresponding to each other andspaced with an interval, and two lateral edges 22 surrounding the outerperiphery of the top and the bottom wall 21, 20, thereby forming a vaporflow channel 23 defined by the top and the bottom wall 21, 20 and thetwo lateral edges 22. The above-mentioned coaxial capillary structure 1can also be processed with a flattening treatment for being able to bedisposed at an inner side of the vapor flow channel 23 and to be incontact with an inner wall of the lateral edge 22 at any side of thepipe body. Because the outer portion of the coaxial capillary structure1 is formed through the coaxially-arranged capillary part 11, thecoaxially-arranged capillary part 11 is able to be in direct contactwith the inner wall of the pipe body (i.e. any of the lateral edges 22or a partial portion of the top and the bottom wall 21, 20), therebyallowing a liquid-state working fluid condensed at other portion of theinner wall of the pipe body to be collected in the coaxial capillarystructure 1, and the liquid-state working fluid is enabled to be guidedinto the primary transferring capillary part 10, so the slits orientedin a linear status and formed between the fiber bundles 100 enable theliquid-state working fluid to be rapidly returned or to be rapidlytransferred to a heating portion (i.e. the vaporization portion) of theultra-thin heat pipe.

Please refer to FIG. 4, if the width of the pipe body of the ultra-thinheat pipe 2 is wide or the amount of working fluid required to betransferred is large, two inner sides of the vapor flow channel 23 canboth be provided with the above-mentioned coaxial capillary structure 1for being respectively in contact with the inner walls of the twolateral edges 22 of the pipe body. As such, the vapor flow channel 23can be formed at a reserved space between the two coaxial capillarystructures 1, and the liquid-state working fluid is allowed to becollected in any of the coaxial capillary structures 1 so as to performthe capillary transferring through the coaxial capillary structure 1.

Please refer to FIG. 5, the coaxial capillary structure 1 can also bedisposed at the center of the vapor flow channel 23 and be in contactwith a partial portion of the top and the bottom wall 21, 20 of the pipebody.

Accordingly, with the above-mentioned structure, the coaxial capillarystructure and the ultra-thin heat pipe structure having the same areprovided.

According to the coaxial capillary structure and the ultra-thin heatpipe structure having the same provided by the present invention, thefiber bundles 100 are substantially arranged in parallel or woven with anon-crossing manner, so under a situation of having the same diameter,the smallest pore and the greatest capillary force can be provided bythe present invention; and under a situation of having the same amountsof the fibers, the occupied volume is minimum, so the occupied space ofthe vapor flow channel 23 is minimum and a smallest flow resistance isprovided. Thus, the present invention provides a capillary structurecapable of forming a better capillary transferring effect and a betterheat transferring effect in a very small space such as the interior ofthe ultra-thin heat pipe.

Although the present invention has been described with reference to theforegoing preferred embodiment, it will be understood that the inventionis not limited to the details thereof. Various equivalent variations andmodifications can still occur to those skilled in this art in view ofthe teachings of the present invention. Thus, all such variations andequivalent modifications are also embraced within the scope of theinvention as defined in the appended claims.

What is claimed is:
 1. A coaxial capillary structure, which is installedin an ultra-thin heat pipe and extended towards the length direction ofa pipe body of the ultra-thin heat pipe, including: a primarytransferring capillary part, composed of a plurality of fiber bundlesfor forming as an integral bundle; and a coaxially-arranged capillarypart, formed through a plurality of weaving wires interwoven and reeledat the exterior of the primary transferring capillary part, therebylimiting each of the fiber bundles at the central portion of thecoaxially-arranged capillary part for forming a compact structure. 2.The coaxial capillary structure according to claim 1, wherein each ofthe fiber bundles and each of the weaving wires are made of metalmaterial or non-metal material of glass or carbon fibers.
 3. The coaxialcapillary structure according to claim 1, wherein the material of whichthe fiber bundles are made is the same or different from the material ofwhich the weaving wires are made.
 4. The coaxial capillary structureaccording to claim 1, wherein the outer diameter of the fiber bundles issmaller than the outer diameter of the weaving wires.
 5. An ultra-thinheat pipe structure having a coaxial capillary structure, including: anultra-thin heat pipe, having a vapor flow channel formed inside a pipebody thereof; and a coaxial capillary structure, installed in the pipebody of the ultra-thin heat pipe and extended towards the lengthdirection thereof, and including: a primary transferring capillary part,composed of a plurality of fiber bundles for forming as an integralbundle; and a coaxially-arranged capillary part, formed through aplurality of weaving wires interwoven and reeled at the exterior of theprimary transferring capillary part, thereby limiting each of the fiberbundles at the central portion of the coaxially-arranged capillary partfor forming a compact structure.
 6. The ultra-thin heat pipe structureaccording to claim 5, wherein the pipe body of the ultra-thin heat pipeis formed with a bottom wall and a top wall corresponding to each otherand spaced with an interval, and two lateral edges surrounding the outerperiphery of the top and the bottom wall, the above-mentioned vapor flowchannel is defined by the top and the bottom wall and the two lateraledges.
 7. The ultra-thin heat pipe structure according to claim 6,wherein the coaxial capillary structure is disposed at the center of thevapor flow channel and only in contact with a partial portion of the topand the bottom wall.
 8. The ultra-thin heat pipe structure according toclaim 6, wherein the coaxial capillary structure is disposed at an innerside of the vapor flow channel and in contact with an inner wall of anyof the lateral edges.
 9. The ultra-thin heat pipe structure according toclaim 8, furthering including one more coaxial capillary structure, andthe one more coaxial capillary structure is disposed at another innerside of the vapor flow channel and in contact with an inner wall of theother lateral edge.
 10. The ultra-thin heat pipe structure according toclaim 5, wherein each of the fiber bundles and each of the weaving wiresare made of metal material or non-metal material of glass or carbonfibers.
 11. The ultra-thin heat pipe structure according to claim 10,wherein the material of which the fiber bundles are made is the same ordifferent from the material of which the weaving wires are made.
 12. Theultra-thin heat pipe structure according to claim 10, wherein the outerdiameter of the fiber bundles is smaller than the outer diameter of theweaving wires.